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SQL Server I/O Basics Chapter #1

SQL Server According to Bob

Stable media is commonly physical disk storage, but other devices and certain caching facilities qualify as well. Many high-end disk subsystems provide high-speed cache facilities to reduce the latency of read and write operations. This cache is often supported by a battery-powered backup facility.

Servers 40
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Front-End Performance Checklist 2019 [PDF, Apple Pages, MS Word]

Smashing Magazine

Keep in mind that a good performance picture covers a set of performance metrics, lab data and field data : Synthetic testing tools collect lab data in a reproducible environment with predefined device and network settings (e.g. Real User Monitoring ( RUM ) tools evaluate user interactions continuously and collect field data (e.g.